The reaction from friends, family and fans on social media was as swift as it was diverse.

Tom Hanks, the star and producer of That Thing You Do! sent a heartfelt Tweet about the songwriter with whom he worked on the 1996 film, and even referred to the fictional band in the film, The Oneders. "There would be no Playtone without Adam Schlesinger, without his That Thing You Do!," Hanks wrote, referring to his own company. "He was a One-der. Lost him to COVID-19. Terribly sad today."

Rachel Bloom, the star of My Crazy Ex-Girlfriend and co-writer of many of the more than 125 songs he wrote for the show, wrote, "I have so much to say about Adam Schlesinger that I am at a complete loss for words. He is irreplaceable."

Comedian and host Stephen Colbert from CBS' The Late Show and Comedy Central's The Colbert Report worked with Schlesinger on several occasions, including the Christmas special and soundtrack that won the songwriter his Grammy. "I'm so saddened to hear of the death of Adam Schlesinger due to COVID-19. From the Dana Carvey show to A Colbert Christmas Special, he was a great (and patient) and talented artist with whom it was my good luck to work. Peace."

Rick Springfield, an elder statesman of all things power pop, wrote: "Adam Schlesinger was one talented man and the world will be a less tuneful place without him. I wrote a few songs with him when I was living in New York and he had a brilliant gift for melody. Love and healing to his family."

Governor Phil Murphy of Schlesinger's home state of New Jersey — the Fountains of Wayne was a gardening emporium near the late artist's home — wrote: "From his work with @fountainsofwayn to his award-winning credits in TV, movies, and stage, millions of fans caught that radiation vibe Adam Schlesinger was groovin' on. A sad, sad loss for Jersey's music scene."

Actor Jon Bernthal of Walking Dead and Wolf of Wall Street fame was Schlesinger's cousin. Though there is no update yet on his social media sites, after news of Schlesinger's illness broke on March 31, Nernthal offered kind words and remembrances. "As a little boy I would be mesmerised by his talent. He showed me how cool it was to be an artist."

Aline Brosh McKenna, a friend of Schlesinger and a co-writer on Crazy Ex-Girlfriend, shared a long and moving remembrance on Twitter, along with a demo of one of Schlesinger's songs.

Author Stephen King offered condolences and called Schlesinger, "a fine singer, witty and satiric songwriter. How terrible to lose him at 52 to this virus." King then called "Hey Julie" from Fountains of Wayne one of his favourites. "The Clarity. The humour."

Actor and singer Darren Criss (Glee,) wrote on Twitter that: "For those of you who know my life as a songwriter — Adam Schlesinger's career was always a big source of inspiration for me. He had a lyrical cheekiness that was only matched by his expert understanding of form, and was always able to fuse the two in a really fun, accessible way."

Sadie Dupuis of Speedy Ortiz wrote on Twitter, in tribute to one of her favorite songwriters, that: "A few years ago i noticed Adam Schlesinger followed me, i did the uncool move of DMing to say i'd been a fan since i was a kid — from that thing you do, Josie soundtrack, Fountains of Wayne, more. He messaged back, couldn't have been more encouraging + kind. RIP to a songs hero."

In a later response, Dupris wrote, "his songs are literally the reason i learned guitar. unbelievable talent."

Steve Greenberg, head of the S-Curve Records label that released several Schlesinger-related albums, wrote a series of tweets. "Adam had a killer instinct for writing great, hooky pop songs & he could apply that talent to any situation where such songs were needed."